90 engine in 91 shell

[90tsiawdturbo]

There's a lot of info on swapping 91+ harness into a 90 but I haven't really found what I'm looking for...ok I have a 90 tsi awd and I just bought my buddies clean 91 gsx with transmission..I'm putting my motor in his car and am confirming what the differences are: CAS, throttle body, transistor, and coil correct?
I'm still deciding if I should use his 91 OFH or if I should use my 90 one with external cooler? Also just got a stainless feed line and I think I'm going feed oil to the turbo from the OFH as well... I have both my car an his engine to pull parts from is there anything else I should swap while I'm at it? Also Im not too familiar with dsmlink, do I have to buy it all over again? Or can my chip be swapped to the 91 ecu

 

[19Eclipse90]

There's a lot of info on swapping 91+ harness into a 90 but I haven't really found what I'm looking for...ok I have a 90 tsi awd and I just bought my buddies clean 91 gsx with transmission..I'm putting my motor in his car and am confirming what the differences are: CAS, throttle body, transistor, and coil correct?

Swap those items and it is plug and play; it should have everything it needs to run and drive with the '91 ECU.

I'm still deciding if I should use his 91 OFH or if I should use my 90 one with external cooler?

Remember if you change OFHs you should also change thermostat housings and water pipes. The downside to the '91 OFH is that it does have the water cooling unit that, if cracked, can allow the coolant and oil to mix; not that this happens often, but it is a possibility. That also isn't to say the '90 OFH is perfect either, it's ultimately up to you which way you'd like to go.

Also just got a stainless feed line and I think I'm going feed oil to the turbo from the OFH as well...

Make sure you're sending the correct pressure of oil and that it is from a filtered port on the housing.

Also Im not too familiar with dsmlink, do I have to buy it all over again? Or can my chip be swapped to the 91 ecu

Carrying over a '90 ECU to a '91? Swap pins 6 and 14. Be aware your tach may not work with the '90 ECU.

 

[90tsiawdturbo]

Couldn't have asked for a better response thanks you very much sir!! Although I have not heard of changing the tstat and water pipe...I'll have to check into the swap, although I think I like the idea of the 90 OFH a bit more...also the stainless line does have a restrictor

 

[19Eclipse90]

...Although I have not heard of changing the tstat and water pipe...I'll have to check into the swap...

If you have the parts, there's no reason not to swap the thermostat housing and water pipe. Without the '91+ OFH, there is no need for an additional feed from the thermostat housing to the cooling unit on the '91+ OFH. It follows that, if there is no feed, there is no need for a return. The return from the cooling unit on the '91+ OFH is on the '91+ water pipe.

The '90 turbo thermostat housing has one less port than the '91+ turbo and the '90 water pipe, aside from the normal in from the lower radiator hose and out to the water pump, has only the coolant return from the turbo to worry about.

 

[90tsiawdturbo]

That's all on my 90 engine still so I might as well run the 90 OFH anyhow....

 

[dsmcurse]

All DSM's use oil-to-water style oil cooler with the exception of 1990 and japan 4g63 equipt cars like gallant. The 1990/japan oil-to-air oil cooler is rare and highly sought after. The 91+ oil-to-water oil coolers use hot engine water to cool the hot engine oil. Theres more lil coolant lines to go bad and have problems with. The 1990 oil-to-air oil cooler is basically a front mount intercooler for your engine oil. The air cooled oil cooler works alot better. Fresh air cooling it is alot better, plus you can upgrade the cooler to a larger unit with more surface area which also raises you oil fill level. I have the japan oil cooler with a upgraded cooler (huge B&M tranny cooler) thats front mount right behind my intercooler. Raised my oil capacity from 4qts to 5. Definatley go thru the trouble and effort to use the 1990 cooler vs the water cooled one.